Diff: CAN/CAN_com.cpp

Revision:

42:738fa01b0346

Child:

52:8e74c22ed89f

Child:

54:59575833d16f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CAN/CAN_com.cpp	Fri May 25 15:16:42 2018 +0000
@@ -0,0 +1,71 @@
+#include "CAN_com.h"
+
+
+ #define P_MIN -12.5f
+ #define P_MAX 12.5f
+ #define V_MIN -45.0f
+ #define V_MAX 45.0f
+ #define KP_MIN 0.0f
+ #define KP_MAX 500.0f
+ #define KD_MIN 0.0f
+ #define KD_MAX 5.0f
+ #define T_MIN -18.0f
+ #define T_MAX 18.0f
+ 
+
+/// CAN Reply Packet Structure ///
+/// 16 bit position, between -4*pi and 4*pi
+/// 12 bit velocity, between -30 and + 30 rad/s
+/// 12 bit current, between -40 and 40;
+/// CAN Packet is 5 8-bit words
+/// Formatted as follows.  For each quantity, bit 0 is LSB
+/// 0: [position[15-8]]
+/// 1: [position[7-0]] 
+/// 2: [velocity[11-4]]
+/// 3: [velocity[3-0], current[11-8]]
+/// 4: [current[7-0]]
+void pack_reply(CANMessage *msg, float p, float v, float t){
+    int p_int = float_to_uint(p, P_MIN, P_MAX, 16);
+    int v_int = float_to_uint(v, V_MIN, V_MAX, 12);
+    int t_int = float_to_uint(t, -T_MAX, T_MAX, 12);
+    msg->data[0] = CAN_ID;
+    msg->data[1] = p_int>>8;
+    msg->data[2] = p_int&0xFF;
+    msg->data[3] = v_int>>4;
+    msg->data[4] = ((v_int&0xF)<<4) + (t_int>>8);
+    msg->data[5] = t_int&0xFF;
+    }
+    
+/// CAN Command Packet Structure ///
+/// 16 bit position command, between -4*pi and 4*pi
+/// 12 bit velocity command, between -30 and + 30 rad/s
+/// 12 bit kp, between 0 and 500 N-m/rad
+/// 12 bit kd, between 0 and 100 N-m*s/rad
+/// 12 bit feed forward torque, between -18 and 18 N-m
+/// CAN Packet is 8 8-bit words
+/// Formatted as follows.  For each quantity, bit 0 is LSB
+/// 0: [position[15-8]]
+/// 1: [position[7-0]] 
+/// 2: [velocity[11-4]]
+/// 3: [velocity[3-0], kp[11-8]]
+/// 4: [kp[7-0]]
+/// 5: [kd[11-4]]
+/// 6: [kd[3-0], torque[11-8]]
+/// 7: [torque[7-0]]
+void unpack_cmd(CANMessage msg, ControllerStruct * controller){
+        int p_int = (msg.data[0]<<8)|msg.data[1];
+        int v_int = (msg.data[2]<<4)|(msg.data[3]>>4);
+        int kp_int = ((msg.data[3]&0xF)<<8)|msg.data[4];
+        int kd_int = (msg.data[5]<<4)|(msg.data[6]>>4);
+        int t_int = ((msg.data[6]&0xF)<<8)|msg.data[7];
+        
+        controller->p_des = uint_to_float(p_int, P_MIN, P_MAX, 16);
+        controller->v_des = uint_to_float(v_int, V_MIN, V_MAX, 12);
+        controller->kp = uint_to_float(kp_int, KP_MIN, KP_MAX, 12);
+        controller->kd = uint_to_float(kd_int, KD_MIN, KD_MAX, 12);
+        controller->t_ff = uint_to_float(t_int, T_MIN, T_MAX, 12);
+    //printf("Received   ");
+    //printf("%.3f  %.3f  %.3f  %.3f  %.3f   %.3f", controller->p_des, controller->v_des, controller->kp, controller->kd, controller->t_ff, controller->i_q_ref);
+    //printf("\n\r");
+    }
+